02543cam a22002657 4500001000700000003000500007005001700012008004100029100002100070245016900091260006600260490004200326500002000368520130100388530006101689538007201750538003601822690009501858690010801953700002202061710004202083830007702125856003802202856003702240w15347NBER20161209203109.0161209s2009 mau||||fs|||| 000 0 eng d1 aKovash, Kenneth.10aProfessionals Do Not Play Minimaxh[electronic resource]:bEvidence from Major League Baseball and the National Football League /cKenneth Kovash, Steven D. Levitt. aCambridge, Mass.bNational Bureau of Economic Researchc2009.1 aNBER working paper seriesvno. w15347 aSeptember 2009.3 aGame theory makes strong predictions about how individuals should behave in two player, zero sum games. When players follow a mixed strategy, equilibrium payoffs should be equalized across actions, and choices should be serially uncorrelated. Laboratory experiments have generated large and systematic deviations from the minimax predictions. Data gleaned from real-world settings have been more consistent with minimax, but these latter studies have often been based on small samples with low power to reject. In this paper, we explore minimax play in two high stakes, real world settings that are data rich: choice of pitch type in Major League Baseball and whether to run or pass in the National Football League. We observe more than three million pitches in baseball and 125,000 play choices for football. We find systematic deviations from minimax play in both data sets. Pitchers appear to throw too many fastballs; football teams pass less than they should. In both sports, there is negative serial correlation in play calling. Back of the envelope calculations suggest that correcting these decision making errors could be worth as many as two additional victories a year to a Major League Baseball franchise, and more than a half win per season for a professional football team. aHardcopy version available to institutional subscribers. aSystem requirements: Adobe [Acrobat] Reader required for PDF files. aMode of access: World Wide Web. 7aD01 - Microeconomic Behavior: Underlying Principles2Journal of Economic Literature class. 7aD82 - Asymmetric and Private Information • Mechanism Design2Journal of Economic Literature class.1 aLevitt, Steven D.2 aNational Bureau of Economic Research. 0aWorking Paper Series (National Bureau of Economic Research)vno. w15347.4 uhttp://www.nber.org/papers/w1534741uhttp://dx.doi.org/10.3386/w15347